Jeremy, This maps on quite well with some of the other implementations I have seen. For example, in Mule they have the concept of connectors that provide transport level abstractions which are decoupled from the UMOs (a.k.a services). Mule uses its own message routing mechanism to associate a connector to a service (I assume in the SCA world this would be a binding to a reference). I think this is also very similar in the JBI world as well, where the NMR decouples the binding components from the service engine components.
Ta Meeraj -----Original Message----- From: Jeremy Boynes [mailto:[EMAIL PROTECTED] Sent: 10 July 2006 16:15 To: tuscany-dev@ws.apache.org Subject: Host API, was: Support for callbacks On Jul 10, 2006, at 7:53 AM, Jim Marino wrote: > > On Jul 10, 2006, at 7:40 AM, Jeremy Boynes wrote: > >> On Jul 10, 2006, at 7:19 AM, Jim Marino wrote: >>> 2. We need to get the host API supporting callbacks. The reference >>> would use the host API to register itself as a listener with a >>> binding as opposed to talking directly with the binding. >>> This will allow us to decouple the callback infrastructure from >>> particular bindings. Jeremy may have some thoughts on this. >>> >> >> I would have though that the reference would register with the >> binding rather than the host. After all the reference is bound on the >> outbound side so is coupled to the binding at that point; wouldn't >> the inbound side just be the reverse? > Wouldn't the reference (composite reference) use the host api to > register with the binding transport? I may not have worded things > clear enough. This way we separate the protocol binding and callback > mechanisms from the particular transport (e.g. Jetty)? In my mind, the host API is a low-level API that allows Tuscany services to connect to physical things in the host environment; examples for physical things would be sockets or things layered on top of sockets (such as servlets, mail-lets, JMS message listeners), threads, timers, etc. The host API would be bridged to a managed environment such as a J2EE server or could be implemented by other low-level Tuscany services such as a Jetty transport or ActiveMQ message broker to provide a standalone environment. Think of it as a host abstraction layer. Things that represent Tuscany or SCA services would sit at a level above that. So, for example, a HTTP transport would sit at this level and would use the host API to register for inbound HTTP requests or to make outbound HTTP requests; a SOAP protocol handler would sit on top of the HTTP transport, a WebService binding would sit on top of a SOAP protocol handler, and so forth. This is a system connection level. The associated between a reference and a binding is a Tuscany concept rather than a physical one so in my mind that would be a connection at the system level rather than at the host level. We still get the decoupling from the physical side (e.g. from Jetty vs. Tomcat) but it's through the stack that the binding is using rather than at the host level. This also means that the reference would be abstracted from the details of the binding (e.g. which SOAP stack, which databinding, which transport). -- Jeremy --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] This message has been checked for all email viruses by MessageLabs. ***************************************************** You can find us at www.voca.com ***************************************************** This communication is confidential and intended for the exclusive use of the addressee only. You should not disclose its contents to any other person. If you are not the intended recipient please notify the sender named above immediately. Registered in England, No 1023742, Registered Office: Voca Limited Drake House, Three Rivers Court, Homestead Road, Rickmansworth, Hertfordshire, WD3 1FX This message has been checked for all email viruses by MessageLabs. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
